Humanity's Current Dilemma

“ ... It took Britain half the resources of the planet to achieve its prosperity; how many planets will a country like India require ... ?”—Mahatma Gandhi, when asked if, after independence, India would attain British standards of living

Historically, the recognition by humans of their impact upon the earth has consistently lagged behind the magnitude of the damage they have imposed, thus seriously weakening efforts to control this damage. Even today, technological optimists and others ignore the mounting evidence of global environmental degradation until it intrudes more inescapably upon their personal welfare. Even some serious students draw comfort from the arguments that:

Previous predictions of environmental catastrophe have not been borne out.

Each of these statements is correct. However, not one of them is a reason for complacency, and indeed, taken together, they should be viewed as powerful evidence of the need for an innovative approach to environmental analysis and management. GDP and other current measures of national income accounting are notorious for overweighting market transactions, understating resource depletion, omitting pollution damage, and failing to measure real changes in well-being (see Section 3.5). For example, the Index of Sustainable Economic Welfare[2] shows much reduced improvement in real gains, despite great increases in resource depleting throughput (see Section 3.5, Figure 3.3). Increases in life expectancies in many nations, by contrast, clearly indicate improvements in welfare; but unless accompanied by corresponding decreases in birth rates, they are warnings of acceleration in population growth, which will compound all other environmental problems. In the former USSR, sharply increasing infant mortality rates and actual declines in life expectancy attest to the dangers of massive accumulations of pollution stocks and neglect of public health[3].

The divergence in views among scientists concerning the greenhouse effect underscores the pervasiveness of uncertainty about the basic nature of our ecological life-support systems and emphasizes the need for building precautionary minimum safe standards into environmental policies. The fact that some environmental problems have been overestimated and that the magnitude of any one of these problems can be denied or debated does not reduce the urgency of our responsibility to seek the underlying patterns from many indicators of what is happening to the “balance of the earth”[4].

Only recently, with advances in environmental sciences, global remote sensing, and other monitoring systems, has a more comprehensive assessment of local and global environmental deterioration become possible. Evidence is accumulating with respect to accelerating loss of vital rain forests, species extinction, depletion of ocean fisheries, shortages of fresh water in some areas and increased flooding in others, soil erosion, depletion and pollution of underground aquifers, decreases in quantity and quality of irrigation and drinking water, and growing global pollution of the atmosphere and oceans, even in the polar regions[5]. Obviously the exponential growth of human populations is rapidly crowding out other species before we have begun to understand fully our dependence upon species diversity. Although post-Cold War conflicts such as those in Haiti, Somalia, Sudan, and Rwanda are characterized in part by ethnic differences, territorial overcrowding and food shortages are contributing factors and consequently provide additional early warning of accumulating global environmental problems.

Clearly, remedial policy responses to date have been local, partial, and inadequate. Early policy discussions and the resulting responses tended to focus on symptoms of environmental damage rather than basic causes and policy instruments tended to be ad hoc rather than carefully designed for efficiency, fairness, and sustainability. For example, in the 1970s emphasis centered on end-of-pipe pollution control which, while a serious problem, was actually a symptom of expanding populations and inefficient technologies that fueled exponential growth of material and energy throughput while threatening the recuperative powers of the planet’s life-support systems.

As a result of early perceptions of environmental damage, much was learned about policies and instruments for attacking pollution. These insights will help in dealing with the more fundamental and intractable environmental issues identified here.

The basic problems for which we need innovative policies and management instruments include:

unsustainably large and growing human populations that exceed the carrying capacity of the earth

highly entropy-increasing technologies that deplete the earth of its resources and whose unassimilated wastes poison the air, water, and land

As emphasized throughout this work, these problems are all evidence that the material scale of human activity exceeds the sustainablecarrying capacity of the earth. We argue that in addressing these problems, we should adopt courses based upon a fair distribution of resources and opportunities between present and future generations as well as among groups within the present generation. These strategies should be based upon an economically efficient allocation of resources that adequately accounts for protecting the stock of natural capital. This section examines the historical record and the emerging transdiscipline of ecological economics for guidance in designing policies and instruments capable of dealing with these problems.

Historically, severe anthropogenic damage to some regions of the earth began as soon as humans learned to apply highly entropy-increasing technological processes to agriculture and was sharply escalated by factory production in Europe during the industrial revolution. Early public policy responses were feeble to nonexistent, allowing polluters whose political and economic power began to eclipse that of the feudal magnates to gain de facto property rights to emit wastes into the common property resources of air and water. In England, it was not until urban agglomeration in London with its choking smog from coal fires so discomforted Parliament that forceful action was taken. In the mid-twentieth century, incidents of deaths from smog, the result of automobiles and modern industry, began to occur. In Donora, Pennsylvania, in the U.S. in 1948 a “killer smog” produced by a steel mill operating during a week-long temperature inversion killed several people and caused illness in the thousands. In London several thousand people were killed during one winter night in 1952 as a result of the smog from domestic and industrial coal burning. Eventually these incidents led to the passage of clean air legislation and improved technologies.

Even more massive loss of life from the spread of water-borne diseases continued to be accepted as part of the human condition until advances in scientific knowledge concerning the role of microorganisms prompted sewage treatment and water purification systems. Vast urban expenditures on such systems eventually reduced the enormous loss of human life from the uncontrolled discharge of human waste into common property waterways. The application of appropriate science, appropriate technology, and community will was necessary to reduce the costly loss of human life that had resulted from unprecedented population expansion, the concentration of humans into unplanned urban areas, and uncompensated appropriation of common property resources for waste disposal.

Homo sapiens is at another turning point in its relatively long and (so far) inordinately successful history. Our species’ activities on the planet have now become of so large a scale that they are beginning to affect the ecological life-support system itself. The entire concept of economic growth (defined as increasing material consumption) must be rethought, especially as a solution to the growing host of interrelated social, economic, and environmental problems. What we need now is real economic and social development (qualitative improvement without growth in resource throughput) and an explicit recognition of the interrelatedness and interdependence of all aspects of life on the planet (see Section 3.3 for more on this important distinction between growth and development). We need to move from an economics that ignores this interdependence to one which acknowledges and builds upon it. We need to develop an economics that is fundamentally ecological in its basic view of the problems that now face our species at this crucial point in its history.

As we show in Section 2, this new ecological economics is, in a very real sense, a return to the classical roots of economics. It is a return to a point when economics and the other sciences were integrated rather than academically isolated as they are now. Ecological economics is an attempt to transcend the narrow disciplinary boundaries that have grown up in the last 90 years in order to bring the full power of our intellectual capital to bear on the huge problems we now face.

The current dilemma of our species can be summarized in ecological terms as follows: We have moved from an early successional “empty world” (empty of people and their artifacts, but full of natural capital) where the emphasis and rewards were on rapid growth and expansion, cutthroat competition, and open waste cycles, to a maturing “full world” (see Figure 1.1) where the needs, whether perceived by decision makers or not, are for qualitative improvement of the linkages between components (development), cooperative alliances, and recycled “closed loop” waste flows.

Can we recognize these fundamental changes and reorganize our society rapidly enough to avoid a catastrophic overshoot? Can we be humble enough to acknowledge the huge uncertainties involved and protect ourselves from their most dire consequences? Can we effectively develop policies to deal with the tricky issues of wealth distribution, population prudence, international trade, and energy supply in a world where the simple palliative of “more growth” is no longer a solution? Can we modify our systems of governance at international, national, and local levels to be better adapted to these new and more difficult challenges?

Homo sapiens has successfully adapted to huge challenges in the past. We developed agriculture as a response to the limits of hunting and gathering. We developed an industrial society to adapt to the potential of concentrated forms of energy. Now the challenge is to live sustainably and well but within the material limits of a finite planet. Humans have an ability to conceptualize their world and foresee the future that is more highly developed than that of any other species. We the authors hope that we, the human species, can use this skill of conceptualization and forecasting to meet the new challenge of sustainability. Ecological economics seeks to meet that challenge.

The Global Ecosystem and the Economic Subsystem

A most useful indicator of the magnitude of our environmental predicament is population times per capita resource consumption[6]. This is the scale of the human economic subsystem with respect to that of the global ecosystem on which it depends, and of which it is a part. The global ecosystem is the source of all material inputs feeding the economic subsystem, and is the sink for all its wastes. Population times per capita resource consumption is the total flow—throughput—of resources from the ecosystem to the economic subsystem then back to the ecosystem as waste, as shown in Figure 1.1. The upper diagram illustrates the bygone era when the economic subsystem (depicted by a square) was small relative to the size of the global ecosystem. The lower diagram depicts a situation much nearer to today in which the economic subsystem is very large relative to the global ecosystem.

The global ecosystem’s source and sink functions have large but limited capacity to support the economic subsystem. The imperative, therefore, is to maintain the size of the global economy to within the capacity of the ecosystem to sustain it. It took all of human history to grow to the $600 billion/yr scale of the economy of 1900. Today, the world economy grows by this amount every two years. Unchecked, today’s $16 trillion/yr global economy may be five times bigger only one generation or so hence.

It seems unlikely that the world can sustain a doubling of the material economy, let alone the Brundtland Commission’s called for “five- to ten-fold increase”[7]. Throughput growth is not the way to reach sustainability; we cannot “grow” our way into sustainability. The global ecosystem, which is the source of all the resources needed for the economic subsystem, is finite and has limited regenerative and assimilative capacities. While it now looks inevitable that the next century will be occupied by double the number of people in the human economy consuming resources and burdening sinks with their wastes, it seems doubtful that these people can be supported sustainably at anything like current Western levels of material consumption. We have already begun to bump up against various kinds of limits to continued material expansion. The path to sustainable future gains in the human condition will be through qualitative improvement rather than quantitative increases in throughput.

From Localized Limits to Global Limits

The economic subsystem has already reached or exceeded important source and sink limits. We have already fouled parts of our nest and there is practically nowhere on this earth where signs of the human economy are absent. From the center of Antarctica to Mount Everest human wastes are obvious and increasing. It is not possible to find a sample of ocean water with no sign of the 20 billion tons of human wastes added annually. PCBs (polychlorinated-biphenyls), other persistent toxic chemicals like DDT, and heavy metal compounds have already accumulated throughout the marine ecosystem. One fifth of the world’s population breathes air more poisonous than World Health Organization (WHO) standards recommend, and an entire generation of Mexico City children may be intellectually stunted by lead poisoning.

Since the Club of Rome’s 1972 “Limits to Growth,” the emphasis has shifted from source limits to sink limits. Source limits are more open to substitution, are more amenable to private ownership, and are more localized. Consequently, they are more amenable to control by markets and prices. Sink limits involve common property where markets fail. Since 1972, the case has substantially strengthened that there are limits to throughput growth on the sink side[8]. Some of these limits are tractable and are being tackled, such as the CFC phaseout under the Montreal Convention. Other limits are less tractable, such as increasing CO2 emissions and the massive human appropriation of biomass. Another example is landfill sites, which are becoming extremely difficult to find. Garbage is now shipped thousands of miles from industrial to developing countries in search of unfilled sinks. It has so far proved impossible for the U.S. Nuclear Regulatory Commission to rent a nuclear waste site for US$100 million. Germany’s Kraft-Werk Union signed an agreement with China in 1987 to bury nuclear waste in Mongolia’s Gobi Desert. These facts confirm that landfill sites and toxic dumps—aspects of sinks—are increasingly hard to find. One important limit is the sink constraint of fossil energy use. Therefore, the rate of transition to renewable energy sources, including solar energy, parallels the rate of the transition to sustainability. Technological optimists also add the possibility of cheap fusion energy by the year 2050. In the face of such high-stakes uncertainty, we should be agnostic on technology. We should encourage sustainable technological development but not bank on it to solve all environmental problems. Since research has only just begun to focus on input reduction and has focused even less on sink management, there is probably the most scope for dramatic technological improvements in these areas.

First Evidence of Limits: Human Biomass Appropriation

The best evidence that there are imminent limits is the calculation by Vitousek et al.[9] that the human economy uses—directly or indirectly—about 40% of the net primary product of terrestrial photosynthesis today. (This figure drops to 25% if the oceans and other aquatic ecosystems are included.) And desertification, urban encroachment onto agricultural land, blacktopping, soil erosion, and pollution are increasing, as is the search for food by expanding populations. This means that in only a single doubling of the world’s population (say 40–45 years) we will use 80%, and 100% shortly thereafter. As Daly[10] points out, 100% appropriation is ecologically impossible, but even if it were possible, it would be socially undesirable. The world will go from half-empty to full in one doubling period, irrespective of the sink being filled or the source being consumed.

Second Evidence of Limits: Climate Change

The second evidence that limits have been exceeded is climate change. The year 1990 was the warmest year in more than a century of record-keeping. Seven of the hottest years on record all occurred in the last 11 years. The 1980s were 1?F warmer than the 1880s, while 1990 was 1.25?F warmer. This contrasts alarmingly with the preindustrial constancy in which the earth’s temperature did not vary more than 2?–4?F in the last ten thousand years. Humanity’s entire social and cultural infrastructure over the last 7000 years has evolved entirely within a global climate that never deviated as much as 2?F from today’s climate[11].

It is too soon to be absolutely certain that global change has begun; normal climatic variability is too great for absolute certainty. There is even greater uncertainty about the possible effects. But all the evidence suggests that global change may well have started, that CO2 accumulation started years ago as postulated by Svante Arrhenius in 1896, and that it is worsening fast. Scientists now practically universally agree that such change will occur, although differences remain on the rates and impacts. The U.S. National Academy of Science warned that global change may well be the most pressing international issue of the next century. A dwindling minority of scientists remain agnostic. The dispute concerns policy responses much more than the predictions.

The scale of today’s fossil fuel-based human economy is the dominant cause of greenhouse gas accumulation. The biggest contribution to greenhouse warming, carbon dioxide released from burningcoal, oil, and natural gas, is accumulating in the atmosphere. Today’s 5.8 billion people annually burn the equivalent of more than one ton of coal each.

Next in importance contributing to climate change are all other pollutants released by the economy that exceed the biosphere’s absorptive capacity: methane, CFCs, and nitrous oxide. Relative to carbon dioxide these three pollutants are orders of magnitude more damaging, although their amount is much less. Today’s market price to polluters for using atmospheric sink capacity for carbon dioxide disposal is zero, although the real opportunity cost may turn out to be astronomical. Economists are almost unanimous in persisting in externalizing the costs of CO2 emissions, even though by 1993 more than 180 nations had signed a treaty to internalize such costs.

There may be a few exceptions to the negative impacts of global warming, such as plants growing faster in CO2-enriched laboratories where water and nutrients are not limiting. However, in the real world, it seems more likely that crop belts will not shift quickly enough with changing climate, nor will they grow faster because some other factor (e.g., suitable soils, nutrients, or water) will become limiting. The prodigious North American breadbasket’s climate may indeed shift north, but this does not mean the breadbasket will follow because the deep, rich prairie soils will stay put, and Canadian boreal soils and muskeg are very infertile.

The costs of rejecting the greenhouse hypothesis, if true, are vastly greater than the costs of accepting the hypothesis if it proves to be false. By the time the evidence is irrefutable, it is sure to be too late to avert unacceptable costs, such as the influx of millions of refugees from low-lying coastal areas (55% of the world’s population lives on coasts or estuaries), damage to ports and coastal cities, increases in storm intensity, and most important of all, damage to agriculture. The greenhouse threat is more than sufficient to justify action now, even if only in an insurance sense. The question now to be resolved is how much insurance to buy.

Admittedly, uncertainty prevails. But uncertainty cuts both ways. Given the size of the stakes involved, “business as usual” or “wait and see” is an imprudent, if not foolhardy, strategy. Although underestimation of climate change or ozone shield risks is just as likely as overestimation, recent studies suggest we are consistently underestimating risks. In May 1991, the U.S. EPA upped by 20-fold their estimate of UV-cancer deaths, and the earth’s ability to absorb methane was revised downwards by 25% in June 1991. In the face of uncertainty about global environmental health, prudence should be paramount.

The relevant component here is the tight relationship between carbon released and the scale of the material economy. Global carbon emissions have increased annually since the industrial revolution, they are now at nearly 4%/yr. To the extent energy use parallels economic activity, carbon emissions are an index of the scale of the material economy. Fossil fuels account for 78% of U.S. energy.

Reducing fossil energy intensity is possible in all industrial economies and in the larger developing economies such as China, Brazil, and India. Increasing energy use without increasing CO2 means primarily making the transition to renewables: biomass, solar, and hydroelectric power. The other major source of carbon emissions—deforestation—also parallels the scale of the economy. More people needing more land push back the frontier. But such geopolitical frontiers are rapidly vanishing today.

The seven billion tons of carbon released each year by human activity (from fossil fuels and deforestation) accumulate in the atmosphere, and carbon accumulation appears for all practical purposes to be irreversible. Hence it is of major concern for the sustainability of future generations. Removal of carbon dioxide by liquefying it or chemically scrubbing it from stacks might double the cost of electricity. At best, technology may reduce, but not eliminate, this major cost.

Third Evidence of Limits: Ozone Shield Rupture

The third evidence that global limits have been reached is the rupture of the ozone shield. It is difficult to imagine more compelling evidence that human activity has already damaged our life-support systems than the cosmic holes in the ozone shield. That CFCs would damage the ozone layer was predicted as far back as 1974 by Sherwood Rowland and Mario Molina. But when the damage was first detected—in 1985 in Antarctica—disbelief was so great that the data were rejected as coming from faulty sensors. Retesting and a search of hitherto undigested computer printouts confirmed that not only did the hole exist in 1985, but that it had appeared each spring since 1979. The world had failed to detect a vast hole that threatened human life and food production and that was more extensive than the United States and taller than Mount Everest.

The single Antarctic ozone hole has now gone global. All subsequent tests have proved that the global ozone layer is thinning far faster than models predicted. A second hole was subsequently discovered over the Arctic, and recently ozone shield thinning has been detected over both North and South temperate latitudes, including over northern Europe and North America. Furthermore, the temperate holes are edging from the less dangerous winter into the spring, thus posing more of a threat to sprouting crops and to humans.

The relationship between the increased ultraviolet “b” radiation let through the impaired ozone shield and skin cancers and cataracts is relatively well known: every 1% decrease in the ozone layer results in 5% more of certain skin cancers. This is already alarming in certain regions (e.g., Queensland). The world seems destined for 1 billion additional skin cancers, many of them fatal, among people alive today. The possibly more serious human health effect is depression of our immune systems, increasing our vulnerability to an array of tumors, parasites, and infectious diseases. In addition, as the shield weakens, crop yields and marine fisheries decline. But the gravest effect may be the uncertainty, such as upsetting normal balances in natural vegetation. Keystone species—those on which many others depend for survival—may decrease, leading to widespread disruption in environmental services and accelerating extinctions.

The one million or so tons of CFCs annually dumped into the biosphere take about 10 years to waft up to the ozone layer, where they destroy it with a half-life of about one century. Today’s damage, although serious, only reflects the relatively low levels of CFCs released in the early 1980s. If CFC emissions cease today, the world still will be gripped in an unavoidable commitment to ten years of increased damage. This would then gradually return to predamage levels over the next century.

This shows that the global ecosystem’s sink capacity to absorb CFC pollution has been exceeded. Since the limits have been reached and exceeded, mankind is in for damage to environmental services, human health, and food production. Eighty-five percent of CFCs are released in the industrial north, but the main hole appeared in Antarctica in the ozone layer 20 kilometers up in the atmosphere, showing the damage to be widespread and truly global in nature.

Fourth Evidence of Limits: Land Degradation

Land degradation is not new. Land has been degraded by civilization for thousands of years, and in many cases previously degraded land remains unproductive today. But the scale has mushroomed and is important because practically all (97%) of our food comes from land rather than from aquatic or ocean systems. Since 35% of the earth’s land already is degraded, and since this figure is increasing and largely irreversible in any time scale of interest to society, such degradation is a sign that we have exceeded the regenerative capacity of the earth’s soil source.

Pimentel et al.[12] and Kendall and Pimentel[13] found soil erosion to be serious in most of the world’s agricultural areas and that this problem is worsening as more marginal land is brought into production. Soil loss rates, generally ranging from 10 to 100 t/ha/yr, exceed soil formation rates by at least tenfold. Agriculture is leading to erosion, salinization, or waterlogging of possibly 6 million hectares per year. This is a crisis that may seriously affect the sustainability of the world’s food supply.

Exceeding the limits of this particular environmental source function raises food prices and exacerbates income inequality at a time when one billion people are already malnourished. As one third of developing country populations now face fuelwood deficits, crop residues and dung (needed for fertilizer) are diverted from agriculture to fuel. Fuelwood overharvesting and this diversion intensify land degradation, hunger, and poverty.

Fifth Evidence of Limits: Biodiversity Loss

The scale of the human economy has grown so large that there is no longer room for all species in the ark. The rates of takeover of wildlife habitat and of species extinctions are the fastest they have ever been in human history and are accelerating. The world’s richest species habitat, tropical forest, has already been 55% destroyed, and the current rate of loss exceeds 168,000 square kilometers per year. As the total number of species extant is not yet known to the nearest order of magnitude (5 million or 30 million or more), it is impossible to determine precise extinction rates. However, conservative estimates put the rate at more than 5000 species of our inherited genetic library irreversibly extinguished each year. This is about 10,000 times as fast as pre-human extinction rates. Less conservative estimates put the rate at 150,000 species per year[14]. Many find such anthropocentrism to be arrogant and immoral. It also increases the risks of overshoot. Built-in redundancy is a part of many biological systems, but we do not know how near we are to the thresholds.

Population and Poverty

Poverty stimulates population growth. Direct poverty alleviation is essential; business as usual on poverty alleviation is irresponsible. MacNeill[15] states it plainly: “...reducing rates of population growth ...” is an essential condition to achieve sustainability. This is as important, if not more so, in industrial countries as it is in developing countries. Industrial countries overconsume per capita, consequently overpollute, and so are responsible for by far the largest share of our approach to the limits. The richest 20% of the world consumes over 70% of the world’s commercial energy. Twenty-five nations already have essentially stable population size, so it is not utopian to expect others to follow.

Developing countries contribute to exceeding limits because they are so populous today (77% of the world’s total) and because their populations are increasing far faster than their economies can provide for them (90% of world population growth). Real incomes are declining in some areas. If left unchecked, it may be halfway through the 21st century before the number of births will fall back even to current high levels. Developing countries’ population growth alone would account for a 75% increase in their commercial energy consumption by 2025, even if per capita consumption remained at current inadequate levels[16]. These countries need so much scale growth that this can only be freed up by the transition to sustainability in industrial countries.

The poor must be given the chance, must be assisted, and will justifiably demand to reach at least minimally acceptable material living standards by access to the remaining natural resource base. When industrial nations switch from input growth to qualitative development, more resources and environmental functions will be available for the South’s needed growth. It is in the interests of developing countries and the world commons not to follow the fossil fuel model. It is in the interest of industrial countries to subsidize alternatives. This view is repeated by Dr. Qu Wenhu of The Chinese Academy of Sciences, who says: “...if ‘needs’ include one automobile for each of a billion Chinese, then is impossible....” Developing populations account for only 17% of total commercial energy use now, but unchecked this will almost double by 2020[17].

Merely meeting unmet demand for family planning would help enormously. Educating young females and providing them with credit for productive purposes and employment opportunities are probably the next most effective measures. A full 25% of U.S. births and a much larger number of developing country births are to unmarried or teenage mothers who provide less child care. Many of these births are unwanted, which also tends to result in less care. Certainly, international development agencies should assist high population growth countries to reduce to world averages as an urgent first step, instead of trying only to increase infrastructure without population measures.

Beyond Brundtland

To the extent that the economic subsystem both has become large relative to the global ecosystem on which it depends and is exceeding the regenerative and assimilative capacities of sources and sinks, the growth called for by the Brundtland report will dangerously exacerbate surpassing the limits outlined above. Opinions differ. MacNeill[18] claims “a minimum of 3% annual per capita income growth is needed to reach sustainability during the first part of the next century,” and this would require higher growth in national income, given population trends. Hueting[19] disagrees, concluding that for sustainability “...what we need least is an increase in national income.” Sustainability will be achieved only to the extent quantitative throughput growth stabilizes and is replaced by qualitative development, holding inputs constant or even reducing them. Remembering that the scale of the economy is population times per capita resource use, both per capita resource use and population must decline.

Brundtland is excellent on three of the four necessary conditions for sustainability: first, producing more with less (e.g., conservation, efficiency, technological improvements, and recycling); second, reducing the population explosion; and third, redistribution from overconsumers to the poor. Brundtland was probably being politically astute in leaving fuzzy the fourth necessary condition. This is the transition from input growth and growth in the scale of the economy over to qualitative development, holding the scale of the economy consistent with the regenerative and assimilative capacities of global life-support systems. In several places the Brundtland report hints at this. Qualitatively improved assets replace depreciated assets, and births replace deaths, so that stocks of wealth and people are continually renewed and even improved[20]. A developing economy is one that is getting better, not necessarily bigger, so that the well-being of the (stable) population improves. An economy growing in throughput is only getting bigger, exceeding limits, and damaging the self-repairing capacity of the planet.

The poor need an irreducible minimum of basics: food, clothing, and shelter. These basics require throughput growth for poor countries with compensating reductions in such growth in rich countries. Apart from colonial resource drawdowns, industrial country growth historically has increased markets for developing countries’ raw materials, hence presumably benefiting poor countries. But it is industrial country growth that has to contract to free up ecological room for the minimum growth needed in poor country economies. Tinbergen and Hueting[21] put it plainest: “...no further production growth in rich countries... .” All approaches to sustainability must internalize this constraint if the crucial goals of poverty alleviation and halting damage to global life-support systems are to be approached.

Toward Sustainability

As economies change from agrarian through industrial to more service-oriented, throughput growth may change to growth that is less damaging to sources and sinks (for example, coal and steel to fiber optics and electronics). We must shift rapidly to production which is less throughput-intensive. We must accelerate technical improvements in resource productivity, Brundtland’s “producing more with less.” Presumably this is what the Brundtland Commission and subsequent follow-up authors[22] label “growth, but of a different kind.” Vigorous promotion of this trend will indeed help the transition to sustainability and is probably essential. It is also largely true that conservation and efficiency improvements and recycling can be made profitable the instant environmental externalities (e.g., carbon dioxide emissions) are internalized.

But this approach, while necessary, will be insufficient for four reasons[23]. Because of the inescapable laws of thermodynamics, all material growth consumes resources and produces wastes, even Brundtland’s unspecified new type of growth. First, to the extent we have reached limits to the ecosystem’s regenerative and assimilative capacities, throughput growth exceeding such limits will not herald sustainability. Second, the size of the service sector relative to the production of goods has limits. Third, even many services are fairly throughput-intensive, such as tourism, higher education, and health care. And fourth, and highly significant, is that less throughput-intensive growth is “hi-tech”; hence the one place where there has to be more growth—tiny, impoverished, developing-country economies—is less likely to be able to afford Brundtland’s “new” growth.

The Fragmentation of Economics and the Natural Sciences

Before tackling the difficult questions raised in the previous sections, let us first analyze why they are such difficult questions in the first place. A large part of the problem lies in the way we have organized our intellectual activities. The problems outlined above are global, long term, and they involve many academic disciplines and especially the connections between disciplines. The academic disciplines are today very isolated from each other and this contributes to the difficulty of addressing the questions posed above. But it was not always so.

Until roughly the beginning of the 20th century, economics and the other sciences were relatively well integrated. There were relatively few scientists then and one could argue that they had to talk across disciplines just to have someone to talk to. But then there was a shift in worldview. Newtonian physics became the dominant academic paradigm. Its view of the world as linear, separable, mechanical subsystems that could be easily aggregated to yield the behavior of the whole system encouraged the fragmentation of science into separate disciplines. There was also the size problem. As academia and the total body of knowledge grew, it became increasingly difficult to deal with it as a whole. For convenience it had to be ever more finely subdivided.

The next section of the book traces the early, prefragmentation history of economics and the “natural” sciences as they continually interacted with each other. Ecology emerged as a science only in the mid-20th century around the ideas of holism and system integration. It departed from the Newtonian physics model to develop a worldview that is adapted to deal with complex living systems. It is evolutionary and nonlinear and acknowledges the inability to scale by simple aggregation[24]. “Ecology” in this sense is becoming the dominant scientific paradigm and it is an inherently interdisciplinary, “systems” perspective. Ecological economics represents an attempt to recast economics in this different scientific paradigm, to reintegrate the many academic threads that are needed to weave the whole cloth of sustainability.